Any new mega-displacement...
Any new mega-displacement liquid-cooled Harley-Davidson motorcycle engine would incorporate some of the technology from the VRSC Rod series V-twin engines.
Is Harley about to join the displacement race? That topic has been buzzing around the internet with the discovery of Environmental Protection Agency (EPA) documents mentioning a 2450cc V-twin engine. With Harley now running at the bottom of the big-twin displacement class, it's only a matter of time before Harley, which was once distinguished by having the largest motorcycle engines on the road, produces a bigger V-twin.
The EPA emissions document in question (scroll down to the last three pages, 8 through 10, of this PDF) shows testing results for liquid-cooled 2450cc and 2000cc Harley-Davidson V-twin engines. Power for the 2450cc version is listed as 98 kilowatts (131 horsepower) at 5000 rpm with 133 newton-meters (98 foot-pounds) of torque at 3500 rpm. The weight (presumably the GVWR) is listed at 1260 pounds. Since the fuel-tank material is listed as nylon, it would presumably be an under-seat style. The fuel-injected engine uses air injection and catalyst to reduce exhaust emissions.
However, don't get too excited yet. The title page (page 7) for this section is labeled as a "Hypothetical Application." There are other hints that the bike is also hypothetical. On the last page, the "Test Date" is listed as July 2007. The names of the bikes Heritage Ultra Tail and Heritage Ultra Tail Special sound more like jokes than anything Harley would bring to market, and a bike with a big, modern engine is unlikely to be called a Heritage. The designations FLHTRSHCE and FLHTR-SE-9 are those of current models, but an engine that different would likely be part of a new family, with new designations. The projected sales figures 34,000 units a year also seems slightly high for a bike that would certainly top $20,000. Finally, we doubt that any major vehicle manufacturer would permit such sensitive info to be released on a public website.
We expect to see larger Harley V-twins (and possibly other configurations) in the not-too-distant future (maybe even by the end of this month), but we aren't counting on this being one of them.